I recently bought some lm13700. I plan to build the vcf and vca modules, but I can’t find a complete schematic for a good volt per octave vco/vclfo. Anybody have one?
I found a few via Google, though not sure if this is exactly what you’re looking for.
https://modwiggler.com/forum/viewtopic.php?t=162820
https://sinneb.github.io/p597/
There’s also an oscillator diagram in the application notes on the Texas Instruments LM13700 datasheet. Hope this helps!
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“I have some LM13700s and need some circuits to use them in” is rather opposite from the usual LM13700 discussions!
The MFOS VCO uses an LM13700, but only for the sine shaper, and in fact it only uses half.
http://musicfromouterspace.com/analogsynth_new/VCO20120618REV0/VCO20120618REV0.html
Technically also a VCO, the MFOS voltage controlled LFO is built around an LM13700:
http://musicfromouterspace.com/analogsynth_new/VCLFO200607/VCLFO200607.php
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That’s what I mean, precisely! Thank you!
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Those are great! Thanks!
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Half? Two sine waves is the step into additive synthesis. Add filters, punch up the artifacts and more. Should we reclassify the LM13700 as another gateway synth drug?
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For me it’s the 555. Got me hooked…
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